Well, these suppliers provide, quite often, QT apps that allow one
to configure their devices. They need to first locate them. A
network broadcast is what they would like to do. Except on Linux
this requires root permissions.

I'm not at all sure, but isn't this managed with capabilities? There
is a CAP_NET_BROADCAST (although the man page says "unused").

You have my attention. Where is this?

Well, maybe start with "man capabilities". I think that is where I saw
CAP_NET_BROADCAST mentioned. I have never played with any of this, but
my understanding is that you can manage various capabilities on a
per-process or per-user basis. I'm grasping at straws, but I'm sure
somebody here will have an actual understanding of this.